There will be one 'main' Wordpress site using the plugin that will need to be able to communicate with 'children' sites that use the plugin.
The main website will have the domains of the 'children' stored in its database as well as some basic token that will be stored individually in each child site and all of the children's tokens will be stored in the main site's database.
I need to create a PHP file that will be responsible for communication between those sites.
Once that is done, the 'main' site will need to send every new post to all the child sites. Then the child sites will receive that post, keep it idle for a bit, modify it and then post it.
How do I make such communication? Any ideas are welcome because I currently have no idea how to approach it!